Can transfer valve with pressurized seat



Aug. 28, 1956 w. PECHY 2,760,702

CAN TRANSFER VALVE WITH PRESSURIZED SEAT Filed July 28, 1953 2Sheets-Sheet 2 INVENTOR. WIL'LIAM PECHY 0/ 6/45 ATTORNEYS United StatesPatent CAN TRANSFER VAQEETWI'II-I PRESSURIZED William Pechy, Belmar, N.J., assignor to American Can Company, New York, N. Y., a corporation ofNew Jersey Application July 28, 1953, Serial No. 370,726

6 Claims. (Cl. 226-68) The present invention relates to a container orcan transfer mechanism and has particular reference to rotating transfervalves used for passing cans into and out of pressurized compartments ofcan closing machines.

Machines used for closing cans under a vacuum or a gas pressure usuallyare equipped with rotary cylindrical transfer valves having peripherallydisposed and spaced pockets for receiving the cans during transfer intoand out of a pressurized closing compartment. In some machines only acan vacuum or gassing operation is required while in other machines thecans are first vacuumized and then gassed before closing. In order toincrease the efiiciency of such machines initial or preliminaryvacuumizing and/or gassing of the cans is effected during their transferwhile the cans are in the valve pockets.

Since a slight annular clearance space between the valve and itscylindrical seat is required to provide for free rotation of the valve,free or atmospheric air usually passes between the valve and its seatand leaks into the valve pockets during the prevacuumizing and/orpregassing operation with the result that the vacuum and/ or gas isdiluted or reduced and the efficiency of the machine impaired.

The instant invention contemplates overcoming this difficulty byvacuumizing and/or gassing the space between the valve and its seat toprevent leakage of air into the valve pockets.

An object of the instant invention is the provision of a rotary valvecan transfer mechanism for pressurized compartments wherein any spacebetween the valve and its seat is pressurized to prevent leakage of airinto the valve pockets so as to increase the efiiciency ofprepressurizing the pockets and the cans therein during their transfer.

Another object is the provision of such a transfer mechanism whereinsufiicient space between the valve and its seat may be obtained topermit of free rotation of the valve with a resulting decrease in thewearing of the valve and seat faces without leakage of air through thespace and into the valve pockets.

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following description, which, takenin connection with the accompanying drawings, discloses a preferredembodiment thereof.

Referring to the drawings:

Figure l is a vertical section taken through a rotary valve can transfermechanism embodying the instant invention, with parts broken away;

Fig. 2 is a reduced scale horizontal section taken substantially alongthe line 22 in Fig. 1, with parts broken away;

Fig. 3 is a view similar to Fig. 1 and illustrating a modified form ofthe invention, and

Fig. 4 is a view similar to Fig. 2 and taken substantially along theline 44 in Fig. 3.

As a preferred or exemplary embodiment of the in- Patented Aug. 28, 1956stant invention the drawings illustrate a rotary transfer mechanism fora can closing machine of the character disclosed in United States Patent2,039,338 issued May 5, 1936 to R. E. J. .Nordquist et al. on VacuumClosing Machine. In such a machine filled cans are passed, by way of arotary transfer mechanism, from the outside atmosphere into a vacuumizedcompartment for sealing and are then passed, by way of another rotarytransfer mechanism, from the vacuumized compartment back into theatmosphere for shipment and storage.

In the preferred form of the invention shown in Figs. 1 and 2, therotary transfer mechanism comprises a rotary transfer valve 11 disposedadjacent a can transfer opening 12 in a housing 13 enclosing aconventional pres surized closing compartment 14, preferably containinga gas under pressure, into which filled cans A preferably with their topclosures loosely applied are passed for final sealing in the usualmanner. For the purposes of this specification the word pressurized isintended to cover a gas under positive pressure or a vacuum which isnegative pressure. The valve 11 preferably is mounted on a ball bearing16 and a thrust bearing 17 carried on a stationary upright shaft orsupport 18 secured to a frame 19 constituting a portion of the mainframe of the closing machine.

The valve 11 is rotated in a clockwise direction as viewed in Fig. 2 bya ring gear 21 which preferably is an itnegral part of the valve andwhich meshes with a driving pinion 22 carried on a vertical shaft 23journaled in a bearing 24 formed in the frame 19. The shaft 23 is drivenin any suitable manner in time with the other parts of the closingmachine. Pockets 26 are formed in the valve 11 at spaced intervalsaround its periphery for carrying the cans A.

The transfer valve 11 preferably has a tapered outer face and rotates ina correspondingly tapered cylindrical valve seat 29 formed in a curvedor cylindrical wall section 31, which seat is open at its top and bottomends. This wall section 31 constitutes a portion of a housing for thevalve and preferably extends out from the closing compartment housing 13on each side of the can transfer opening 12. An inlet opening 34 formedin the wall section 31 provides for feeding the filled cans A in anysuitable manner into the valve pockets 26 for transfer into the gassingcompartment 14. It is these openings 12 and 34 that are sealed by thevalve 11 to prevent outside free or atmospheric air from entering thepressurized closing compartment 14 and reducing the vacuum or dilutingthe gas contained therein.

As a filled can A, preferably carrying a loose top closure, is receivedin a valve pocket 26 for transfer into the gassing compartment 14, andis carried around toward the can transfer opening 12, the pocket 26 andthe head space within the can preferably are successively prevacuumizedand pregassed to eliminate as much as possible of the free air whichenters the pocket while it is exposed to the outside atmosphere while atthe inlet opening 34 during the reception of the can A.

Prevacuumizing of the pockets 26 preferably is effected by a pair ofspaced ports 36, 37 formed in the valve seat wall section 31. Theseports are connected by pipes 38, 39 to any suitable source of vacuum. Asthe pockets 26 pass the ports 36, 37 the air is exhausted from them andthe cans therein.

Where sealing of the cans A in the compartment 14 is to be effectedunder vacuum, the desired vacuum condition is maintained in thecompartment and usually a lower vacuum is maintained in the pipes 38, 39to only partially exhaust the air from the pockets 26. Under theseconditions no gas is used. Where the cans are to be sealed in a gaseousmedium, for example carbon dioxide or other suitable gas, thecompartment 14 contains such a gas, usually under a predeterminedpressure.

Under such latter condition of sealing the cans in a gaseous medium, thecans A are usually prevacuumized in their valve pockets 26 as explainedabove and are also pregassed while still in their pockets before beingdelivered into the gassing compartment 14. This pregassing of thepockets 26 as the valve rotates is effected by a port 41 formed in thevalve seat wall section 31 and located between the vacuum port 37 andthe can transfer opening 12 in the housing 13. A pipe 42 connects thegassing port 41 to a suitable source of gas under pressure.

When a can A is prevacuumized and pregassed and advanced to a positionopposite the can transfer opening 12 in the housing 13, it is pushed outof its pocket 26 and into the compartment 14 for sealing. This iseffected by a discharge finger 44. There is one of these fingers 44 ineach valve pocket 26 and they are mounted on individual upright rockershafts 45 carried in upper and lower bearings 46 formed in the valve 11.

Each of the rocker shafts 45 extends above the valve 11 and carries acam arm 47 having on its outer end a cam roller 48. All of the camrollers 48 operate in a cam groove 49 formed in a stationary cover plate51 which is disposed over the top end of the valve 11 and which at itsouter edge is bolted to the top edge of the valve seat wall section 31.As the valve 11 rotates, the cam rollers 48 traverse the cam groove 49which is shaped to rock the rocker shafts 45 and discharge fingers 44 atthe proper time.

Provision is made for the free rotation of the valve 11 relative to itsseat 29 without leakage of free or atmospheric air past the valve sothat this air is prevented from entering the valve pockets 26 duringtheir travel from the can inlet opening 34 to the compartment entranceopening 12. To effect this free rotation of the valve 11, the thrustbearing 17 is utilized to support the full load of the valve and aslight annular clearance space 53 is provided between the outer face ofthe valve and the cylindrical valve seat 29. This space 53 ispressurized with a fluid medium to keep it free of air. For this purposethe top and bottom areas of the valve 11 at the opposite ends of thevalve and the open ended cylindrical valve seat 29 are fully enclosedand pressurized.

Above the valve 11, the cover plate 51 seals off the space within thevalve seat 29, the cover plate being recessed to provide a closedchamber 55 disposed above the valve and in complete communication withthe upper end of the annular clearance space 53 between the valve andits seat. The cover plate 51 is provided with a port 56 which isconnected by a pipe 57 and T-fitting 58 to two pipes 59, 69 respectivelyleading from a source of vacuum and a source of gas under pressure. ShutOff valves 61, 62 in the respective pipes 59, are provided to create avacuum or introduce gas into the chamber 55 as required.

In a similar manner the bottom end of the transfer valve 11 is fullyenclosed by a surrounding skirt 63 which extends down from the housing13 and the valve seat Wall section 31 and fits against a flat websection 64 of the machine frame 19. The skirt 63 and web section 64 setoff a closed chamber 65 which is in complete communication with thelower end of the annular clearance space 53, and in which chamber thebottom end of the valve 11 and the valve seat 29, as well as the supportshaft 18, thrust bearing 17, and valve actuating or driving pinion 22are disposed. A port 66 in the web section 64 provides for vacuumizingor gassing the chamber 65 as required. This port is connected by a pipe67 and T-fitting 68 to two pipes 69, 70 provided with shut off valves71, 72 and leading respectively from a source of vacuum and a source ofgas.

Hence if the cans A are to be sealed under vacuum in the sealingcompartment 14, the chambers 55, 65 above and below the transfer valve11 are vacuumized through A the opening of the shut off valves 61, 71 invacuum pipes 59, 69 and thus a vacuum is created in the chambers 55, 65.Since these chambers 55, 65 communicate respectively with the upper andlower ends of the annular clearance space 53 between the transfer valve11 and its cylindrical seat 29, any free air that seeps into this spacethrough the can inlet opening 34 is rapidly exhausted through thechambers 55, 65. Hence this free air is prevented from leaking into thevalve pockets 26 while they are being prevacuumized during theirrotation toward the can transfer or inlet opening 12 intothe pressurizedclosing compartment 14.

If the cans A are to be sealed under gas pressure in the sealingcompartment 14, the chambers 55, 65 may be similarly pressurized withgas if desired, through the closing of the vacuum shut off valves 61, 71and the opening of the gas shut off valves 62, 72. This admits gas underpressure into the chambers 55, 65 and thereby fills the annular space 53between the transfer valve 11 and its seat 29 with gas which excludesoutside free air from the space.

Hence in either case, the outside free air is prevented from leakingthrough the space 53 between the transfer valve 11 and its seat 29 intothe can pockets 26 of the valve with the result that very little if anyfree air is introduced into the sealing compartment 14 with the cans Aas they are delivered thereto for sealing. At the same time the annularspace 53 may be of such proportions as to permit free rotation of thetransfer valve 11 with the result that less friction induced wear isincurred by the valve and its seat and less power is needed to rotatethe valve. This greatly increases the efficiency of the machine andmaintenance of a vacuum or gas pressure condition in the can sealingchamber 14.

As a modified form of the invention, Figs. 3 and 4 of the drawingsillustrate a form of transfer valve 11 in which radial spider webs 81(Fig. 4) are utilized to provide spaced vertical channels 82 through thecentral portion of the valve. These channels 82 extend from one end ofthe valve to the other and effect continuous and uninterruptedcommunication between the upper chamber 55 and the lower chamber 65 sothat only one of these chambers need be connected with sources of vacuumand gas. In Fig. 3 the drawing shows the web section 64 having a port 83which is connected by a pipe 84 and T-fitting 85 to two pipes 86, 87having shut oif valves 88, 89 and leading respectively to a source ofvacuum and a source of gas. Hence the one port 83 serves both chambers55, 65 with the same result as mentioned above in connection with thepreferred form of the invention. If desired the port 83 may be providedin the cover plate 51 instead of in the frame web section 64.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the form, construction andarrangement of the parts without departing from the spirit and scope ofthe invention or sacrificing all of its material advantages, the formhereinbefore described being merely a preferred embodiment thereof.

I claim:

1. In a transfer mechanism for containers, the combination of a housingenclosing a pressurized compartment and having a can transfer openingtherein, a rotatable transfer valve disposed adjacent said transferopening for sealing the same, said valve having peripherally disposedspaced pockets for carrying containers to said opening for deliverytherethrough into said compartment, a valve seat surrounding theperiphery of said valve and said transfer opening to provide an annularclearance space between said valve and seat, a closed pressurizedchamber adjacent each end of said valve, said chambers communicatingwith opposite ends of said annular clearance space, and means forpressurizing said chambers to in turn pressurize said communicatingclearance space between said valve and its seat to protect said valvepockets against leakage of atmospheric air thereinto through said space.

2. In a transfer mechanism for containers, the combination of a housingenclosing a pressurized compartment and having a can transfer openingtherein, a rotatable transfer valve disposed adjacent said transferopening for sealing the same, said valve having peripherally disposedspaced pockets for carrying containers to said opening for deliverytherethrough into said compartment, a valve seat surrounding theperiphery of said valve and said transfer opening to provide an annularclearance space between said valve and seat, a closed pressurizedchamber adjacent each end of said valve, said chambers communicatingwith opposite ends of said annular clearance space, and means connectingsaid chambers with a source of vacuum and a source of gas under pressurefor pressurizing said chambers to in turn pressurize said communicatingclearance space between said valve and its seat to protect said valvepockets against leakage of atmospheric air thereinto through said space.

3. In a transfer mechanism for containers, the combination of a housingenclosing a pressurized compartment and having a can transfer openingtherein, a rotatable transfer valve disposed adjacent said transferopening for sealing the same, said valve having an enclosing housing andperipherally disposed spaced pockets for carrying containers to saidopening for delivery therethrough into said compartment, a cylindricalvalve seat on a wall of said valve housing surrounding the periphery ofsaid valve and disposed in spaced relation thereto and also surroundingsaid transfer opening to provide an annular clearance space between saidvalve and seat, said clearance space being open at its opposite ends,means for sealing off the opposite ends of said valve housing to providea closed chamber at each end of said valve, said chambers respectivelybeing in full communication with opposite ends of said annular clearancespace between said valve and said seat, and means for pressurizing saidchambers to in turn pressurize therethrough said communicating clearancespace to protect said valve pockets against ingress of atmospheric airfrom said space.

4. In a transfer mechanism for containers, the combination of a housingenclosing a pressurized compartment and having a can transfer openingtherein, a r0- tatable transfer valve disposed adjacent said transferopening for sealing the same, said valve having an enclosing housing andperipherally disposed spaced pockets for carrying containers to saidopening for delivery therethrough into said compartment, a cylindricalvalve seat on said valve housing surrounding said valve and saidtransfer opening to provide an annular clearance space between saidvalve and seat and open at its opposite ends, a closed pressurizedchamber adjacent each end of said valve, said chambers being independentof each other and respectively in communication with the opposite openends of said clearance space, and means for pressurizing said chambersindependently of each other to in turn pressurize therethrough fromopposite ends of said valve the adjoining ends of said clearance spaceto protect said space and said valve pockets against leakage thereintoof atmospheric air.

5. In a transfer mechanism for containers, the combination of a housingenclosing a pressurized compartment and having a can transfer openingtherein, a rotatable transfer valve disposed adjacent said transferopening for sealing the same, said valve having an enclosing housing andperipherally disposed spaced pockets for carrying containers to saidopening for delivery therethrough into said compartment, said valvefurther having an open channel extending therethrough from one end tothe other, a valve seat on said valve housing surrounding said valve andsaid transfer opening to provide an open ended annular clearance spacebetween said valve and seat, a closed pressurized chamber disposedadjacent each end of said valve, said chambers respectivelycommunicating with opposite ends of said clearance space and valvechannel for communicably connecting said chambers, and means connectedwith one of said closed chambers for pressurizing both of said chambersthrough said valve channel to in turn pressurize said clearance space,thereby protecting said space and said valve pockets against ingress ofatmospheric air.

6. In a transfer mechanism for containers, the combination of a housingenclosing a pressurized compartment and having a can transfer openingtherein, a rotatable transfer valve disposed adjacent said transferopening for sealing the same, said valve having peripherally disposedspaced pockets for carrying containers to said opening for deliverytherethrough into said compartment, a cylindrical housing wall sectionopen at its opposite ends and surrounding said valve and said transferopening, said wall section having a cylindrical seat for said valve andproviding an open-ended annular clearance space therebetween, spacedmeans connected to said wall section and communicating with said valveseat at spaced localities remote from said transfer opening respectivelyfor successively prevacuumizing and pregassing said valve pockets,closure means connected to the opposite open ends of said wall sectionfor sealing said wall section and for providing a closed chamberadjacent each end of said valve, said chambers being respectivelycommunicably connected with the open ends of said clearance space, andmeans for pressurizing said chambers to in turn pressurize therethroughsaid clearance space, thereby protecting said space and saidvalvepockets against leakage thereinto of atmospheric air.

References Cited in the file of this patent UNITED STATES PATENTS

